Studies are progressing on the following projects: 1. Lactose Synthase. In addition to kinetic studies, the role of histidine in the function of alpha-lactalbumin is being examined by modification with diethylpyrocarbamate and the role of acetals in the synthase is being examined. 2. Glycosyl Transferases. Several glycosyl transferases are under study including 3 sialyl transferases, 3 fucosyl transferases, 2 N-acetylgalactosaminyl transferases and a galactosyl transferase. Their enzymic properties are being determined and their role and regulation in oligosaccharide biosynthesis is under study. 3. Mucins, Immunoglobulins, Orosomucoid and Rabbit Liver Lectin. The structure and function of the oligosaccharides in these glycoproteins is being examined with the aid of enzymic modification with glycosyl transferases and glycosidases. BIBLIOGRAPHIC REFERENCES: Purification of a Sialyltransferase from Bovine Colostrum by Affinity Chromatography on CDP-Agarose. J.C. Paulson, W.E. Beranek and R.L. Hill. J. Biol. Chem. (1977) 252, 2356-2362. Purification, Composition, Molecular Weight and Subunit Structure of Ovine Submaxillary Mucin. H.D. Hill, Jr., J.A. Reynolds and R.L. Hill. J. Biol. Chem. (1977) 252, 3791-3798.